Conventionally, micro contactors used for a test for a semiconductor or a test for liquid crystal include a thin plate-shaped probe holder with a number of minute through holes formed therein so as to insert probes that electrically connect a circuit structure of an object of a test and a circuit structure that transmits a signal used for the test. For such a probe holder, a ceramic member (machinable ceramics) having free-machining characteristics is used (for example, refer to Patent Literature 1).